In every scenario and in every situation, the Ultra-X beats down the Zalman CNPS9500 out-of-the-box. As stated previously, the thermal compound may have something to do with this, but we used what came with each cooler to represent the average consumers install. I was very impressed with the noise, performance and overall quality of the Ultra-X cooler. In many situations, it beat out the CNPS9500 by as much as 5C!